Conventionally, a circuit assembly such as a junction box that uses a relay circuit to supply, block, or distribute power, for example, is employed in an electrical component system in an automobile, and is fixed at an appropriate position of an automobile so that it can be used. Also, as disclosed in JP 2012-243449A, electric vehicles, hybrid cars, plug-in hybrid cars, and the like in recent years employ a configuration in which a junction box is housed in a housing of a battery pack together with a battery module, a battery control system, and so on.
Here, as disclosed in JP 2012-243449A, such a junction box housed in a housing and an external wire harness are connected to each other by mating a harness end connector, which is provided at an end of the wire harness, to a housing connector, which is provided on a peripheral wall of the housing, and electrically connecting the housing connector and the junction box in the housing to each other, using a coated electrical wire or a bus bar.
However, such a conventional structure for connecting a wire harness to a circuit assembly in a housing involves a large number of parts that are interposed between the wire harness and the circuit assembly, and therefore a conventional structure needs a large space so that the interposed parts can be housed and arranged therein, and thus faces limitations in satisfying the need for saving space. In addition, an increase in the number of work steps is inevitable due to the number of parts being large, which leads to lower production efficiency.